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I sure don't blame Ken (the OP) for considering a 250/350 truck. It won't hurt anything except comparatively poor fuel economy as a daily driver.
There really isn't a lot of difference between the F-350 and an F-150 though. Under unfavorable conditions even the 350 will fail to keep control. Check
this tired old example out. I guess one might argue a Ford Ranger would have tipped more easily with the trailer, but truck damage is really luck of the draw when an RV goes over.
I did pick up a Hensley Arrow hitch too, primarily because of the original extremely light truck and fear of wind. I finally chose a larger truck myself, skipping over a full 1/2 ton, when I reluctantly decided I needed to buy something bigger than the Ford Ranger to tow our 294RLS trailer.
I think our 29.4 (30) foot RV is around 36 feet total, just as Kens 315RKS is probably rated a 32 footer (31.5 foot cabin), or 38 foot total, hitch-to-bumper. For a couple more feet, I do love his roomy Autumn Ridge bedroom slideout, which we don't have. I know some folks thought his Autumn Ridge had a 38 foot cabin but that is unlikely.
Anyway, our little mini-truck handled the 30' trailer just fine at very moderate speeds, but the main problem was the little V6 didn't guarantee enough power to maintain 45 mph up long hills on the interstate, which I found unacceptable.
My original expectation was to avoid distant travel and stick to 2 lane local rural roads, but friends soon suggested we camp at a distant site not directly available by 2 lanes. Masterplan failed. Otherwise the above linked video says it all, truck size doesn't always matter much. Note the plain hitch didn't even have weight distribution bars, but in this case, they wouldn't have helped anyway. A load of bricks on the trailer floor, or at least full tanks might have helped keep 'er down. As an apparent Park model, it probably had no fresh/holding tanks. It was a total forty-foot boxkite.
The Hensley design does positively prevent wagging sway, but in my experience the whole TV/TT rig (tow vehicle/travel trailer) tends to move sideways (as a straight unit) from passing trucks, as might well a one-piece motorhome under the same conditions. I think the Hensley design exceeds the control that 5th wheel trailers have, and matches a motorhome. Nothing is perfect, however.
Because the Hensley is occasionally a nuisance when hitching up on uneven ground, I took it off and replaced it with the cheapest, quickest WD hitch I could find (EazLift, about $206 with a friction damper) since they all operate the same otherwise (except for the Reese cam, Pullrite and Hensley types). The Hensley is a nice, serene accessory when traveling cross-country in all kinds of weather full time, and I might put it back if I do so. I did get blown over to the shoulder before I had the EazLift adjusted right. This is our second EazLift WD, the first having been sold with our previous 30' camper.
Wes
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